Condylar positional changes after mandibular advancement surgery with rigid internal fixation

The purpose of this retrospective investigation was to describe condylar po sitional changes in patients after mandibular advancement surgery. By super imposing on clearly identifiable cephalometric landmarks tie, mandibular sy mphysis and rigid fixation screws), condylar positional changes from immedi ately after surgery to orthodontic appliance removal were extrapolated. Alt hough the mandibular symphysis generally moved in either an anterior or pos terior direction after surgery, condylar movements were exclusively in an u pward vertical direction. Correlations were found between several measured variables, including a tendency for increased superior postsurgical movemen t of the condyles with increasing magnitudes of surgical advancement of the mandible. This long-term instability of skeletal relationships may be caus ed by a wide variety of interacting factors and events.